Kill a watt type power meter for cheap


6pack

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Looking to buy a kill a watt type power meter for around 1k. I'm seeing chinese brands around 800 on Amazon but most are 2 pin with a hole for earth - like European or such type plugs. Wanted a three pin plug type instrument.

All the Indian brands like Meco or Meko etc are 2k+.

Edit: the electricity meters used by power companies here are rated at 3200imp/Kw hour.
imp = impressions or readings i think.

Whereas, the chinese meters are just 1000imp/Kw hr. Too low.
 
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blr_p

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The key point that matters here is True RMS measurement. Without RMS its not reliable. Cheaper brands are not RMS. Only buy if it specifically states able to measure RMS


I would not cheap out on measuring equipment
 
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blr_p

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I wanted to measure consumption of fridge and my pc and inverter over a month. That's why I wanted to buy one.
Then it would be good to have a model with a battery backup else you lose your data at the next power out

Analog is cheapest in this case. Maybe you can get an old electricity meter that the power company uses and make some sort of rig
 

cute.bandar

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I got one from amazon.in for Rs.1500 . Don't know about RMS, but it seems accurate enough.

BIG NOTE: The 3 pins one I have, DO NOT ACCOMMODATE LARGE PLUGS LIKE THAT OF AC AND FRIDGE. Not checking this was a big oversight on my part :( , as a I had bought it to measure power consumption of AC.
Also (I read) the measuring meter should support 2 to 3 times the power requirement of your device.
 
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blr_p

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If it doesn't say RMS then its not RMS and its using averaging. For power accounting it needs to do RMS of the voltage & then the current and over a period of time. As the video points out.
 

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6pack

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In the downloads section they have software for Windows, Mac and Linux too. They say we can see the readings free from that application.
 

blr_p

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I don't understand how a PC will be able to query a bluetooth meter. Only a wifi enabled one. To be frank i'm more a fan of wifi than bluetooth as routers have far better range and you can check it from further away. But the wifi enabled software is buggy by their admission already. No updates since July 2017. Whereas the BT app got an update Jul this year.
 

6pack

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Is it possible to go completely off grid?

I want a backup plan in case my discom wants me to pay high electricity bills every month even when I haven't used it. I got my meter put in challenge - its gone for lab testing or something. Don't know what the results will be. Temporary meter shows average of 3.5 units per day. Faulty meter showed 30+ per day. So worst case scenario if they don't test it properly and tell me that meter is not faulty and to pay up 10k this and next month, is I tell them to cut my electricity connection completely. 10k per month is not affordable for me.

I can live without fridge and tv. My needs are very few. I've already switched to Led lights and power saving fans / appliances in the past few years. So least items I need besides mobile are just 2 x 9W leds, 1 ceiling fan, 1 table fan for a few hours per week and washing machine because it cleans and dries clothes quiet well. All of these run off my 850VA inverter connected to a 150AH battery. Should I just buy a solar kit or buy parts separately?

Edit: Found this company selling 1.2KWh lithium ion battery pack.

http://www.germansolarasia.com/products4.php

Never heard of them. Is this company real?
 
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Arjun

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This is really drastic step, your usage is so low, you need to ensure that properly functioning meter is installed by them, complain to pgportal and if required consumer court.
 

rdst_1

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Considering such low usage, a solar setup would be near perfect for you.
I have a farm so I'll be shifting to biogas and solar setup gradually as well. Only recurring cost is batteries and even they last 5-8 years depending upon how good care you take of them.
Electricity from my provider is very cheap, but I want to shift so as to stop being reliant on a govt service.
 
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6pack

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I think Luminous is going to sell a lithium battery pack of 930Kwh. How long will these packs last for if used only at night time?
 

adder

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:)Are you sure, since even a Tesla top model S has only 100kwh battery pack.

What luminous offers is over priced.

Lithium batteries have realy high efficiency, but have lower cycle life(typically about 300 cycle) then a 1200 to 1500 cycle Tubular lead acid battery.

There are batteries with bettery chemistry which offer higher cycle life such as LifeP04(1000 to 3000 cycles and LTO battery(5000 to 10000 cycles or more)the latter best suited for solar. No ready made products use them.

You can use a programmable solar inverter , where the charge settings can be adjusted to use the above two battery types.
You will off course need to import the batteries from china, air shipping is not an option.

It needs to be imported by sea, which the common man finds it impossible, unless anyone her have contacts with a reliable shipping agent.
 
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6pack

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:)Are you sure, since even a Tesla top model S has only 100kwh battery pack.

What luminous offers is over priced.

Lithium batteries have realy high efficiency, but have lower cycle life(typically about 300 cycle) then a 1200 to 1500 cycle Tubular lead acid battery.

There are batteries with bettery chemistry which offer higher cycle life such as LifeP04(1000 to 3000 cycles and LTO battery(5000 to 10000 cycles or more)the latter best suited for solar. No ready made products use them.

You can use a programmable solar inverter , where the charge settings can be adjusted to use the above two battery types.
You will off course need to import the batteries from china, air shipping is not an option.

It needs to be imported by sea, which the common man finds it impossible, unless anyone her have contacts with a reliable shipping agent.
Its 960WH, heh heh.


I was looking at these 18650 or 3xxxx type cells on Aliexpress. They cost 60k for a lot of 200 cells. Plus add to that customs and shipping and solar panels, solar setup charges, and other setup charges and it goes above 1 lakh easily. Wonder how long backup the cells will give compared to just solar panels and extra lead acid battery of say 200-400AH.
 

adder

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If your energy load is more at night you will need more batteries, if your energy load is at day you will need more solar panels, so that you can directly run of solar power while still having the batteries at full charge.

If you plan to go off grid, then you will need to calculate the house energy load during a 24 hr period where the solar panels won't be charging batteries which is around 4:30pm to 10:30am varies depending on the region. So for eg in my case fans,tv,router,PC,mobile charging alone will need about 2000w during the period of no solar charging, so just to replenish the battery charge the following day, I would need 500w of solar panels to charge the batteries.

If I want to power devices that run during the day when solar power is available like washing machine, Induction stove,tank water pump, water geyser(solar water heater costs about 35k to 50k for a good one and for that price I can get 1kw to 1.5kw of solar panels), I would need more solar panels about 3kw minimum for direct solar use without using battery, for me to go off grid i would need 5kw so that even a AC can run.

A lithium battery pack of same Ah/voltage will not give more back up time then a lead acid battery pack of same Ah/voltage. The difference is that a 100ah lead acid battery will need about 150ah to recharge to 100 percent. Compare to lithium batteries which only need a little over 100ah to recharge to 100 percent.

A typical 250w solar panel on it's best day and hour will give about 8amps, when they say 250w it's under ideal test condition at a room temperature of 25c. Based on my own finding on average you will get about 200w typically from a 250w panel. With solar inverters now having 95 percent efficiency or more, you will get close to that 200w of AC power. So you can do the math normaly the solar panels produce enough power at around 10:30am for the solar inverter to switch the charger and by 4pm the power again drops as the sun sets.
If there is any shadow falling on the panels due to trees or neigbouring buildings then you are screwed.

If anyone is going solar the bare minimum I would suggest is to get a solar inverter that operates on 24v battery input for powering light loads under 1500w. Recommended to get a 48v battery input for 2kw and upwards (less heat internally, less strain on the components inside the solar charger/solar inverter)and of course higher efficiency.
 
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6pack

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Discom people cut power to my house without even informing me. Even the challenge meter was still there.

I don't when when I'll be back here. Off to buy some solar powered mobile charger on Amazon. If anyone is using one please link here.
 

nimod

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Discom people cut power to my house without even informing me. Even the challenge meter was still there.

I don't when when I'll be back here. Off to buy some solar powered mobile charger on Amazon. If anyone is using one please link here.
amazing!
but why?